Surface-Space Managed Network Fabric

ABSTRACT

A managed surface-space network fabric is presented. The surface-space network fabric can include a spaced-based network fabric and a surface-based network fabric integrated together to form a single fabric managed by a global fabric manager. The global fabric manager cooperates with other fabric managers local to each fabric to establish a communication topology among all the nodes of the fabric. Preferred topologies include paths from any port on a node to any other port on another node in the fabric. The surface-space fabric, and each individual fabric, can function as a distributed core fabric operating as a single, coherent device.

This application claims priority to U.S. provisional application havingSer. No. 61/079,892 filed on Jul. 11, 2008; and this application is acontinuation-in-part of U.S. patent application having Ser. No.12/120,024 filed on May 13, 2008, which claims priority to U.S.provisional application having Ser. No. 61/013,852 filed Dec. 14, 2007,U.S. provisional applications having Ser. Nos. 61/014,306 and 61/014,367filed on Dec. 17, 2007, U.S. provisional application having Ser. No.61/023,004 filed on Jan. 23, 2008, and U.S. provisional applicationhaving Ser. No. 61/024,842 filed on Jan. 30, 2008. These and all otherextrinsic materials discussed herein are incorporated by reference intheir entirety. Where a definition or use of a term in an incorporatedreference is inconsistent or contrary to the definition of that termprovided herein, the definition of that term provided herein applies andthe definition of that term in the reference does not apply.

FIELD OF THE INVENTION

The field of the invention is networking technology involvingspacecraft.

BACKGROUND

Global data communication infrastructure has developed dramatically overthe last several decades. Individuals can currently access data over theInternet from nearly anywhere in the world. Additionally, satellitesallow for point-to-point communications over the horizon of the Earth tosupport global positioning systems (GPS), television broadcasts,military communications, or other surface-to-surface communications.Unfortunately, satellites generally only provide a “bent-pipe”communication between two ground stations as opposed to integrating intoa networked communication system such as the Internet. Bent-pipecommunications suffer from a number of problems, not the least of whichis susceptibility to local jamming at a ground station. If one groundstation is unable to send or receive a signal due to jamming, thecommunication is lost. Loss of an up/down communication link with asatellite during a military operation, a first response to a disaster,or urgent scenario can cause severe loss of life or can causesubstantial financial losses.

Preferably satellites or other spacecraft should form a network in spaceand integrate with a surface network at multiple points in a seamlessfashion to overcome loss of a single up/down communication link.Communications can be reestablished through one or more alternativepaths through the space-based network, the surface-based network, or anycombination. Ideally, the space and the surface-based networks shouldintegrate to form a single surface-space network fabric.

The need for such a surface-space network fabric has been articulatedmultiple times. NASA publication NASA/TM—2004-213109 (AIAA—2004-3253)titled “Developing Architectures and Technologies for an Evolvable NASASpace Communication Infrastructure” by Bhasin et al. describes variousfeatures for an interplanetary communication network. Additionally, theJoint Capability Technology Demonstration (JCTD) program sponsored bythe U.S. Department of Defense (http://www.acq.osd.mil/jctd/) alsoexpressed a need for network communications in space. In 2007,the DoDrequested proposals for a JCTD directed toward Internet Protocol Routingin Space (IRIS). The stated goals of the IRIS JCTD are:

-   -   “In coordination with commercial satellite communications        providers, implements Internet Protocol (IP) routing and dynamic        bandwidth resource allocation capabilities from a geostationary        commercial communication satellite, which enables cross-band,        cross-beam routing. Shows scalability, “any-to-any” connectivity        within the coverage of the satellite, and satellite bandwidth IP        gain. Advances DoD'guidance to grow an IP foundation across the        enterprise and also builds the business model and contracting        processes for DoD to use emerging commercial capabilities.”

The three year program was awarded to Intelsat General Corp of Bethesda,Maryland. Intelsat plans on working with Cisco Systems, Inc. of SanJose, Calif., and SEAKR Engineering Inc. of Denver, Co., to createradiation hardened routers for deployment within a satellite.Unfortunately, little or no results have yet been announced nor does thecontemplated IP network integrate with surface-based fabrics.

Others have also attempted to provide a space-based network. Forexample, U.S. Patent 7,366,125 to Elliot titled “Extensible SatelliteCommunicate System” describes a satellite network where backbonesatellites act as routers for data transmitted through a network.Although useful for allowing satellites to communicate among each other,the contemplated backbone network also fails to integrate into a surfacenetwork. In a similar vein, U.S. Pat. No. 6,078,810 to Olds et al.titled “Multiple-Tier Satellite Communication System and Method ofOperation Thereof” also provides for having satellites transmit data(e.g., media content) among each other. Although useful for distributingmedia content, Olds also fails to provide for integrating space fabricsinto surface fabrics.

U.S. Patent Publication 2008/0043663 to Youssefzadeh et al. titled“Satellite Communication with Multiple Active Gateways” contemplatesthat a master ground station can operate as a gateway to a networkincluding the Internet. Slave ground stations communicate with themaster ground station using TDMA channels relayed through satellites ingeosynchronous orbits. Although Youssefzadeh provides for another masterground station to take over for a failed master, Youssefzadeh fails toprovide for forming a surface-space network fabric.

U.S. Patent Publication 2008/0155070 to El-Damhougy et al. titled“Method of Optimizing an Interplanetary Communications Network”describes a solution for an ad-hoc network having spaced based andground-based nodes where the nodes are located at extreme distances fromEarth. Each node comprises an artificial neural network that allows thenode to self-manage and self-maintain the connectivity of the node. Suchan ad-hoc network can be useful in circumstances where nodes are out ofreach of their human controllers. However, an ad-hoc network lackssufficient determinism for mission critical applications. A strongercentralized management system would be required for mission criticalsurface-space fabrics.

U.S. Patent Publication 2005/0259571 to Battou titled “Self-HealingHierarchical Network Management System, and Methods and ApparatusTherefore” describes managing multiple networks by organizing themanagers of the networks into a hierarchical structure. A root manageroversees the mangers below it in the structure. Should a manager fail,then another manger can take its place. Although useful in asurface-based network, the Battou structure is unsuitable for asurface-space fabric where the space fabric can become decoupled from asurface fabric.

In addition to effort directed toward establishing networks in space,effort has been put forth toward robust protocols for use in space. Forexample, the article titled “Roadmap for Developing ReconfigurableIntelligent Internet Protocols for Space Communication Networks” datedJun. 29, 2004, by Malakooti of Case Western Reserve University'sElectrical Engineering and Computer Science Department describes adevelopment roadmap for an Intelligent Internet Protocol (IIP). Althoughuseful in exchanging data under highly variable conditions in space, IIPalso lacks support for sufficient determinism in a space-surface fabric.

Interestingly, a great deal of efforts has been directed to creating anetwork in space and protocols. Less effort has been directed towardseamlessly integrating such a network with surface-based infrastructure.Little or no effort has been directed toward managing a communicationtopology of an integrated surface-space network in a substantiallydeterministic fashion. What has yet to be appreciated is that asurface-space network fabric can be managed via one or fabric managerswhere any node in the fabric, either a spaced-based node or asurface-based node, can operate as the fabric manager.

Thus, there is still a need for surface-space managed network fabric.

SUMMARY OF THE INVENTION

The present invention provides apparatus, systems and methods in which asurface to space network fabric can be created from multiple networkfabrics working in cooperation with each other. A space-based networkfabric comprising a plurality of spacecraft networking nodes provide acommunication infrastructure whose communication topology is configuredor controlled through a spaced based fabric manager. The space fabriccan be communicatively coupled to a surface-based network fabric havinga surface-based fabric manager. A global fabric manager establishes aglobal communication topology among the spacecraft and the surface-basednodes in cooperation with the various fabric managers. In a preferredembodiment, the nodes of the space and the surface fabric are fungiblewith respect to taking on the roles or responsibilities of theirrespective fabric managers. Additionally, all nodes of the surface-spacefabric can be fungible with respect to the roles or responsibilities ofbeing the global fabric manager.

Spacecraft nodes are located in space (e.g., at altitudes greater than100 Km) moving relative to a surface of the Earth or substantiallystable with respect to positions on the surface. Preferred spacecraftnodes include satellites in geosynchronous orbit. It is alsocontemplated that spacecraft can be placed in lower or higher orbits asdesirable. Furthermore, spacecraft can also be placed at LaGrangepoints.

In some embodiments, a surface-space network fabric can include one ormore intermediary network fabrics comprising intermediary network nodes.Contemplated intermediary network nodes can include low-earth orbit(LEO), powered flight aircraft, or non-powered flight aircraft.

Various objects, features, aspects and advantages of the inventivesubject matter will become more apparent from the following detaileddescription of preferred embodiments, along with the accompanyingdrawings in which like numerals represent like components.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a schematic of a distributed core fabric.

FIG. 2 is a schematic of a surface-space network fabric having a spacefabric and surface fabric managed by a global fabric manager.

FIG. 3 is a schematic of a surface-space fabric comprising anintermediary fabric having intermediary nodes.

DETAILED DESCRIPTION

Although the following description provides examples of network fabricshaving a small number of network nodes, communication links, datachannels, or data paths, it should be noted that a fabric can compriseany number of nodes, data links, or data channels.

Network Fabric Overview

The general concepts of a network fabric as presented herein can beequally applied to a network fabrics located in space or on the surfaceof the Earth, or other massive body. The term “Earth” is used in thisdocument to mean a massive body and should be interpreted to mean amassive body around which another physical object can orbit. Othermassive bodies can include moons, planets, stars (e.g., the Sun),asteroids, comets, or other bodies found in or around a solar system.

In FIG. 1 network fabric 100 comprises a plurality of networked nodes110 interconnected through a plurality of physical communication links120 connecting neighboring network nodes. In a preferred embodiment,each link 120 can support one or more data channels to connect anynetwork node 110 to another node 110. Additionally, data paths can beestablished from one of device 130 to another device 130 utilizing oneor more data channels and one or more data links 120. Network fabricscan include fabrics for internetworking, storage area networks,distributed computing buses, mesh networks, peer-to-peer networks, orother type of network.

Devices 130 can include any system connected to network fabric 100 vianodes 110, and represent end-points for communications. Example devicesinclude computers, set-top boxes, game consoles, storage devices,handheld devices (e.g., mobile phones, PDAs, etc . . . ), sensors,spacecraft, space stations, satellites, or other devices that wouldbenefit from network access. Devices 130 communicate with each otherpreferably sending packets across fabric 100. It should be noted thatdevices 130 are considered to be differentiated from nodes 110 in thatdevices 130 ordinarily lack switching or routing capabilities.

In a preferred embodiment, network nodes 110 comprise devices thatincorporate network switches, that when connected together providesdynamic packet routing across fabric 100, preferably at or below layertwo of the OSI model. Network nodes 110 function as networkinginfrastructure devices having routing information on how to switchpackets among paths available though the nodes. Network nodes 110 shouldnot be confused with a mere relay station (e.g., a satellite offering a“bent pipe” communication). A relay station lacks routing knowledge onhow to switch packets among paths through the network. Although thepreferred embodiment provides a fabric at layer two of the OSI model, itis also contemplated that the inventive subject matter can beadvantageously applied to other layers including layer three of the OSImodel (e.g., IPv4 or IPv6) or above. A fabric operating at layer two orlower offers several advantages. For example, each node can provide forcut-through routing from an ingress port to an egress port within thenode with little or no overhead due to protocol processing overhead.

Links 120 can be wired or wireless as required by deployment of nodes110. For example, nodes 110 deployed on the surface of the Earth can bewired (e.g., Ethernet cables, optic fibers, USB, Firewire, Infiniband,etc . . . ), or wireless (e.g., 802.11, UWB, WiMAX, etc . . . ). Nodes110 deployed at high altitude or in space preferably employ wirelesslinks including radio frequency (RF) links, optical links (e.g.,lasers), or microwave links (e.g., C band, Ku band, Ka band, etc . . .). Preferred links support bandwidths of at least 10 Gbps and latenciesless than 10 microseconds. Additionally, preferred links supportmultiple data channels on a single physical channel. Optic fibers, forexample, represent a suitable link for surface nodes because fibers cansupport high-bandwidth, low-latency data transport on multiple channelswhere each channel corresponds to a different wavelength of light.

Network node 110 should not be considered limited to network switches,Ethernet or otherwise. Rather network nodes 110 can also include otherforms of networking infrastructure including routers, bridges, gateways,access points, repeaters, or other networking devices offeringinterconnectivity.

Preferably, each of links 120 is a port-to-port communications link,wired or wireless, between two connected neighboring nodes 110. In apreferred fabric, each physical link 120 between two nodes 110 can alsosupport multiple data channels. For example, a single optic fiberrepresenting a link between two neighboring network nodes 110 cansupport multiple data channels where each data channel on the opticfiber uses a different wavelength of light to transport data.Additionally, a laser or an RF communication link between to satellitescan support multiple channels.

Multiple links 120 and data channels can be combined to form one or moredata paths from one physical port on a node 110 to another port locatedanywhere on fabric 100. In this sense, a data path should be considereda port-to-port route. A data path can provide data transport usinglow-level protocols, Ethernet or ATM, for example. Additionally, a datapath can support data transport data using high-level protocols (e.g.,IPv4, IPv6, TCP, UDP, etc . . . ) as desired by devices 130.

Data paths are preferably constructed by a fabric manager 115 whoseresponsibilities include storing route tables, disseminating routes, orassigning paths. Co-owned U.S. Pat. No. 7,352,745 titled “Switchingsystem with distributed switching fabric” issued Apr. 1, 2008, describessuitable methods for establishing data paths through a switched fabric.

In a preferred embodiment, fabric 100 comprises a distributed corefabric. Raptor Networks Technology, Inc. of Santa Ana Calif.(http://www.raptor-networks.com/) provides suitable network switches,including the ER-1010 switch, which can be used to create a distributedcore fabric. Multiple ER-1010 switches can be deployed to form adistributed core fabric by connecting the switches through optic fibersto create a packet-switched network. Additionally, the Raptor technologycan be adapted for deployment within spacecraft to support a switchingfabric in space utilizing optical links (e.g, lasers) or RF-based links.As used herein, “distributed core” means a plurality of network nodesoperating as a single coherent device. For example, interconnectedRaptor switches can function as a single large switch.

A distributed core fabric preferably lacks a need for spanning treeprotocol because the network fabric comprises nodes that self-organizeto behave as one coherent device. Once the nodes are organized accordingto a communication topology based on routing tables, data is then routeddynamically through fabric via one or more constructed data paths.

Nodes 110 preferably comprises one or more physical ports through whichdata packets can be exchanged with devices 130 or other nodes 110. Aphysical port can is considered to comprise one or more physicalcomponents capable of receiving or transmitting signals to a neighboringnode 110. Examples include receptacles for wired connections (e.g.,RJ-45 jacks, Firewire connectors, USB connectors, etc . . . ), opticalsensors for sending or receiving laser transmissions, or antennas forreception or transmission of RF or microwave signals. Preferred portsare bi-directional and can both transmit and receive signals.

Preferably, fabric 100 comprises fabric manager 115. In a preferredembodiment, nodes 110 are fungible with respect to being a fabricmanager. Fabric manager 115 preferably comprises one or more softwaremodules adapted to take on management roles or responsibilities withrespect to two or more nodes 110 of fabric 100. Managementresponsibilities can include configuring communication topologies,monitoring fabric metrics, inventorying nodes of the fabric, loggingevents within the fabric, alerting external entities to conditions ofthe fabric, reporting activities of the fabric, recovering from fabricfaults, or enforcing security.

In a distributed core fabric where each node 110 is fungible withrespect to management functions, fabric manager 115 can migrate from onenode 110 to another node 110. Manager migration provides for additionalsecurity within fabric 100 by reducing the risk that an external wouldknow where a manager is located. Manager 115 can migrate indeterministic fashion or non-deterministic fashion. In a preferredembodiment surface fabric managers, space fabric mangers, globalmanagers, or other fabric managers can migrate. Additional discussionwith respect to manager migration can be found in parent, co-owned U.S.patent application having Ser. No. 12/120,024 filed on and titled“Disaggregated Network Management”.

In a preferred embodiment, fabric manager 115 is configured to establisha communication topology among nodes 110 of fabric 100. Within thisdocument, a “communication topology” is considered to comprise aplurality of port-to-port data paths among nodes 110. One should notethat a communication topology is not merely an arrangement of nodes withconnections. Rather, a communication topology also includes the mappingof data paths from a first port to a second port, and could includemultiple paths. Fabric manager 115 assigns paths and establishes arouting table comprising the communication topology information. Manager115 preferably disseminates the information to nodes 110 of fabric 100.Each of node 110 can locally store the topology information and use theinformation to determine internally how to switch a packet arriving atan ingress port to an egress port in order to forward the packet ontoward its final destination port. As previously mentioned, a suitablemethod for assigning paths of a communication topology is discussed inco-owned U.S. Pat. No. 7,352,745 titled “Switching system withdistributed switching fabric” issued Apr. 1, 2008.

A preferred routing table includes a list of the most desirable pathsfrom a port to other ports. In some embodiments, the table includes allpossible paths from all ports to all other ports. Each path can beidentified by a route ID used as an index into a routing table. Aspackets enter fabric 100 from an ingress port, the receiving node 110determines the destination of the packets (e.g., by destination IPaddress, destination MAC address, or other destination ID). Thereceiving node 110 can then select a path from the routing table thatconnects the ingress port to the egress port on fabric 100 that connectsto the destination. The path's route ID can be appended to the packets,and the packets forwarded to the next node 110 on the path. Eachsubsequent node 110 uses the route ID as in index into its local copy ofthe route table to look-up the next hop. The packets are preferablyforwarded until they reach their destination port where the routed ID isstripped from the packets and the packets are presented to thedestination. Should a fault occur along a path where a node is lost, asending node can change the path for a packet by changing the route IDof the packet. The new path referenced by the new route ID preferablypreserves the source and destination while avoiding failed nodes, links,or channels.

Several advantages become clear with respect to switching packets basedon routing tables storing desirable paths. One advantage includes thatpackets can be routed in a cut-through fashion with little or nointroduction of latency. For example a packet can be forwarded quickly(e.g., much less than 10 microseconds) by conducting a quick tablelook-up. An additional advantage includes that the packet transportacross fabric 100 is protocol agnostic. A low-level distributed corefabric provides for a high-capacity (e.g., greater than 10 Gbps), lowlatency (e.g., less than 10 microsecond) communication transport thatcan support any upper layer protocol including Ethernet, IPv4, IPv6,TCP, UDP, or any other protocols.

Surface-Space Network Fabric

In FIG. 2, surface-space network fabric 200 comprises space fabric 240and surface fabric 220. Space fabric 240 is preferably communicativelycoupled to surface fabric 220 by a plurality of up/down links 265. Eachfabric can comprise a fabric manager, space manager 235 or surfacemanager 215, which has responsibility for management of its localfabric. Additionally, in a preferred embodiment, fabric 200 alsocomprises global manager 217 that has management responsibility ofentire surface-space fabric 200.

Space-Based Network Fabric

Space fabric 240 comprises a plurality of spacecraft nodes 230comprising any suitable spacecraft adapted to operate as a networkingnode to form a distributed core fabric. Contemplated spacecraft includesatellites in orbit, probes, space stations, or other spacecraft, mannedor unmanned. Fabric 240 provides a packet switched network capable oftransporting data packet among two or more spacecraft 232A through 232B.

Spacecraft nodes 230 communicate with each other or with one or more ofspacecraft 232A through 232B via spacecraft links 245. Links 245 caninclude optical communication links (e.g., lasers), radiocommunications, or microwave communications. Preferred links 265 cansupport inter-spacecraft communications two or more data channels usingthe same physical link. Techniques known in the art for providingmultiple channels on a link include frequency-division multiple access(FDMA), time-division multiple access (TDMA), code-division multipleaccess (CDMA) or spread spectrum multiple access (SSMA), to name a few.

In a preferred embodiment, a spacecraft is adapted with a fabricswitching module comprising software, hardware, or a combination of boththat enable spacecraft nodes 230 to function as networkinginfrastructure by switching packets entering node 230 on an ingress portto an appropriate egress ports as previously discussed. In someembodiments, a switching fabric is based on Raptor switching technologyadapted for use in space. For example, an ER-1010 Raptor switch can beadapted to be robust against the extremes of space including radiation,heat, cold, vacuum, high-G launch, or against other extremes. It is alsopreferred that a switching module incorporated into spacecraft node 230operate as a fabric manager for space fabric 240, for example spacemanager 235 is both a networking node as well as the manager of fabric240. In this respect, each of spacecraft nodes 230 is fungible withrespect to being the fabric manager. One should also appreciate thatnodes 230 can also operate as a global fabric manager for surface-spacefabric 200. Once a spacecraft has been incorporated with a fabricswitching module, the spacecraft can be launched as desired. In someembodiments, spacecraft nodes 230 include redundant switching modules toprotect against potentially fatal failure of a primary module.

A switching module can also include a software update to existing,suitably equipped spacecraft already deployed in space. The softwareupdate can be loaded into memory on board spacecraft node 230 using anup/down link 265. Once installed, the software update can provide packetswitching capability among data channels for links 245 or links 265.Additionally, the software update can include fabric managementfunctions for configuring a communication topology among nodes 230.

Space fabric manager 235 configures a topology among nodes 230 utilizingport-level information aggregated from nodes 230. Manager 235 uses theport-level information to construct a routing table having assignedpaths from a first port to a second port, preferably multiple paths,anywhere in the fabric. Fabric manager 235 disseminates the routingtable to all other nodes 230. Each node 230 can determine how to forwardpackets at the port-level by consulting the routing table. In thismanner, space fabric manager 235 configures a communication topologyamong nodes 230. It should be noted that the communication topology alsocomprises multiple port-to-port paths for redundancy. Should a node 230loose connectivity, a forwarding node 230 can consult its routing tableto determine an alternative path for a packet.

Spacecraft nodes 230 can form space fabric 240 located anywhere in space(e.g., above 100 Km) as long as nodes 230 can retain some level ofinterconnectivity. For example, spacecraft nodes 230 can be placed inlow-Earth orbit (LEO; up to 2000 Km), medium Earth orbit (MEO; 2000 Kmto about 35,700 Km), geosynchronous orbit (GEO; at about 35,700 Km),high Earth orbit (HEO; more than 35,700 Km), or other orbits. It is alsocontemplated that spacecraft nodes 230 can be placed in orbits that arerelatively stable with respect to Earth's position including LaGrangepoints (e.g., L1, L2, L3, L4, or L5) where the forces of gravity ofmassive bodies (e.g., Earth, Moon, or Sun) are countered by centripetalforce due to the spacecraft's obits. Although the previous orbits arediscussed with reference to the Earth, one skilled in the art willrecognize the orbital altitudes or locations would be different withrespect to another massive body, Mars for example.

In a preferred embodiment of fabric 240, nodes 230 comprise aconstellation of GEO satellites. GEO satellites have reduced relativemovement with respect to each other and with respect to ground stationsallowing for stable, high bandwidth inter-satellite communications. Forexample, geosynchronous satellites can intercommunicate via lasers at 10Gbps. A suitable method for inter-satellite communication using lasersis described in the article titled “Next-Generation Satellite LaserCommunications System”, authored by Hiroo Kunimori, published in theDecember, 2004, issued of NiCT News (No. 345). A geosynchronous fabricprovides for a globally spanning communication network accessible fromnearly anywhere from the planet.

Fabric 240 communicates with one or more surface fabrics 220 located onthe surface of the Earth via a plurality of up/down links 265. Up/downlinks 265 can utilize existing technology to allow nodes 230 tocommunication with nodes 210 of fabric 220. For example, up/down links265 can include RF or microwave communication links, capable ofsupporting more than one data channel. Typical links in use today canemploy the Ka band supporting a few Gbps. Other links in use today usethe C band or Ku band of the electromagnetic spectrum. In a preferredembodiment, up/down links 265 comprise an aggregated link combining morethan one channel to form a high capacity link supporting at least 10Gbps. An up/down link 265 having a bandwidth of 10 Gbps allows the linkto properly bind with commercially available network switching siliconthat can be deployed within switches for surface nodes 210.

Up/down links 265 can connect directly to surface nodes 210 orindirectly through ground stations. Regardless of the means of theconnection, links 265 are consider a physical link connecting nodes viainterconnecting ports. When establishing global communicationtopologies, links 265 are treated as any other links connecting twoports within the fabric. Up/down links 265 connecting surface nodes 210with GEO spacecraft 230 are thought to be relatively stable. If links265 connect surface nodes 210 with spacecraft nodes 230 that are inflight, in low orbit, or in high earth orbit links 265 are expected tobe established, broken, and re-established as necessary. However, suchup/down links are expected to have predictable behavior that can befolded into determining communication topologies without requiring thepaths to be periodically reconstructed as described below.

Surface-Based Network Fabric

Surface fabric 220 comprises a plurality of surface nodes 210interconnected via surface links 225. Surface nodes 220 are consideredto be devices supporting networking infrastructure located substantiallyon the Earth's surface (e.g., within 10 Km of sea level) as opposed tonodes at high altitude, LEO, MEO, GEO, or HEO. Suitable surface nodes220 include switches, routers, access points, gateways, or othernetworking infrastructure as previously discussed.

Links 225 can also comprises wired or wireless links that preferablysupport multiple data channels. In a preferred embodiment, links 255employ optic fibers capable of supporting a bandwidth of at least 10Gbps, or more preferable at least 40 Gbps, over geographicallysignificant distances (e.g., greater than 10 Km).

Surface fabric 220 provides for connectivity among two or more devices212A through 212B. Devices 212A and 212B can include set-top boxes,computers, cell phones, PDAs, game systems, vehicles, or other devicesthat are capable of connecting to fabric 220.

Just a space fabric 240 includes a fabric manager; surface fabric 220also includes a fabric manager, surface manager 215. In a preferredembodiment, each surface node 210 is fungible with respect to beingsurface manger 215. Manager 215 has responsibility for managing fabric220 and can configure a communication topology among the nodes 210.Manger 215 can also operate as the global fabric manager.

Global Fabric Manager

In a preferred embodiment, global manager 217 manages the completesurface-space fabric 200, including surface nodes 210 and spacecraftnodes 230. Global manager 217 operates in a similar manner as localfabric managers 215 and 235 with the exception that it establishes aglobal communication topology among the surface and spacecraft nodes incooperation with surface manager 215 and space manager 235. In fact,global manager 217 establishes a global communication topology thatcomprises paths from a first physical port on a spacecraft node 230 to asecond physical port on a surface node 210, thus allowing a device 212Ato communicate with a spacecraft 232A via the paths. Preferably,Surface-space fabric 200 operates as a single coherent switching devicewhile function under the defined global communication topologyestablished by global manager 217.

Although global manager 217 is depicted as being located on a surfacenode, one should recognize that all nodes 210 and nodes 230 ofsurface-space fabric 200 are fungible with respect to being the globalfabric manager. Additionally, the global fabric manager can operate on anode common as the surface fabric manager or the space fabric manager.For example, global manager 217 could operate on the same node assurface manager 215 or space manager 235.

In some embodiments, global fabric manager 217 aggregates information,including port level information, about nodes 210 and 230 for uses inestablishing the global communication topology. Preferably theinformation is obtained in cooperation with managers 215 and 235, bothof which can obtain information about their local fabric. However, it isalso contemplated that global fabric manager 217 can obtain thenecessary information from each node individually. Once global manager217 establishes a global communication topology in the form of one ormore routing tables, it can disseminate the information to local fabricmanagers 215 and 235. Both local managers can then further disseminatethe information (e.g., routing tables) to their local nodes.

By having global fabric manager 217 work in cooperation with localfabric mangers 215 and 235, surface-space fabric 200 can be globallyoptimized as well as locally optimized. Global manager 217 dictates theover-all communication topology including paths from a spacecraft node230 port to a surface node port 210, and vice versa. Each local manager215 or 235 can be configured accept or reject directives from globalmanager 217 to optimize local fabric links between nodes, or datachannels. It is expected that local manager 215 or 235 could have moreup-to-date information regarding their local nodes and could performlocal optimization that would ordinarily be counter to directives fromglobal manager 217.

Global manager 217 can cooperate with local managers in numerous ways.For example, the local managers can provide their local fabric datadirectly to global manager 217, the local managers can provide localpath assignments with suggestions on up/down links for use, or localmanagers can conduct all local management functions and supplyaggregated information to global manager 217.

It should be appreciated that nodes 210 and 230 are preferably fungiblewith respect to being the global fabric manager. Each of nodes 210 and230 preferably store the complete communication topology information,possibly in the form of one or more routing tables. Should globalmanager 217 loose connectivity, fail, or otherwise become inoperable,any other of nodes 210 or 230 can become the new global manager quickly.In a preferred embodiment, a new global manager can be identified inless than 10 seconds, and more preferably less than 1 second. Given thateach of nodes 210 or 230 has complete topology information, a node canbecome the node global manger nearly instantaneously. Naturally, suchfailover capabilities also apply to local managers 215 and 235.

In some embodiments, global fabric manager 217, surface manager 215, andspace manager 235 could be organized into in a hierarchical managementstructure as suggested by U.S. Patent Publication 2005/0259571 to Battoutitled “Self-Healing Hierarchical Network Management System, and Methodsand Apparatus”. However, due to the potentially dynamic nature ormovement networking nodes 230 (e.g., a LEO satellite) relative to othernodes, space fabric 240 could become decoupled from surface fabric 220periodically causing unnecessary overhead in reorganizing the overallmanagement system. To reduce such overhead, each of fabric 220 and 240can essentially operate as an autonomous fabric under the “suggestion”of global manager 217.

Due to the dynamic nature of up/down links 265, it is possible thatspace fabric 240 could loose connectivity with fabric 220. Consequently,one of space fabric 240 or surface fabric 220 could loose contact withglobal manager 217. Under such conditions, each local manager maintainscoherency of their respective communication topologies. As used herein,“coherency” of the communication topology means that the local managerensures that any viable paths established by the global fabric manager217 are retained until connectivity with the global manager 217 can berestored, or until connectivity via up/down links 265 arere-established.

In a preferred embodiment, global manager 217 establishes the globalcommunication topology and its paths among the ports of surface-spacefabric 200 as a function of fabric metrics or properties. Metrics caninclude measurable values associated with fabric 200 as whole or each oflocal fabric 240 or 220. Contemplated metrics include congestion,throughput, loading, or other measurable values. Properties areconsidered attributes of the fabrics that do not substantially changewith time. For example, a property can include predictable movement ofnodes, or can include latency caused by the speed of light whencommunicating among GEO satellites. Global manager 217 utilizes theinformation for establishing paths from ports on nodes 210 and 230.

One should note that the properties of space fabric 240 could affectcommunications among device 212A, device 212B, spacecraft 232A, orspacecraft 232B. For example, if space fabric 240 comprises aconstellation of GEO satellites intercommunicating using lasers,latencies due to the speed of light could affect protocolcommunications. Latencies could be as high as 500 milliseconds or evenup to 900 milliseconds. Such latencies are thought to have little impacton node-to-node transport of packets in a switching fabric operating ator below layer 3 of the OSI model. However, for high-level protocols orstateful protocols, including TCP, such latencies can cause problems.Therefore, in some embodiments the algorithms used for communicationsamong devices 212 or spacecraft 232 are adjusted to compensate for theproperties of space fabric 240. For example, TCP can be adjusted byusing TCP-LW (large window) to compensate for the large latencies.

In a preferred embodiment, global manager 217 provides an interfacethrough which an administrator is able to manage global manager 217. Theinterface can include web-based applications, remotely accessible APIs,one or more management protocols, or other methods as known in the art.In a preferred embodiment, the interface allows the administrator tocreate or to control a policy comprising one or more rules that governthe establishment of the global communication topology. Although any setof rules can be defined, contemplated advantageous rules include (1)setting priorities for which links or data channels are used in pathassignments, (2) setting bandwidth requirements for port-to-portcommunications, (3) setting latency requirements for port-to-portcommunications, (4) defining security requirements for paths, or (5)manually defined paths through fabric 200.

Global manager 217 can be administered by any suitable authorizedentity, preferably an individual under authority of the United Statesgovernment. Contemplated entities associated with the United Statesgovernment include NASA, FEMA, Department of Defense or its militarybranches, Department of Homeland Security, or other government agenciesor organizations. Such an administrator offers greater protection oroptimization for the transport of mission critical data. Consider, forexample, a scenario where FEMA must response to a disaster. FEMA woulddesire to retain connectivity to all national, or even global, resourcesto maintain logistic channels. An administrator associated with FEMA nomatter their physical location could instruct global manager 217 toestablish one or more redundant paths through fabric 200. The redundantpaths could be manually configured to preferentially employ surfacenodes 210, spacecraft nodes 230, or possibly intermediary nodesspecifically placed during the disaster to facilitate communication.Furthermore, the administrator could configure a communication topologywhere FEMA data traffic is routed through low latency paths (e.g.,through surface nodes or LEO satellites) while low-priority, generaldata traffic is routed through paths having higher latency (e.g., pathsthrough GEO satellites). Global manager 217 can also be controlled oroptimized during military operations, terrorism events, or othercircumstances where connectivity is essential.

Intermediary Network Fabrics and Nodes

One should appreciate that more than two network fabrics can form asurface-space network fabric. In FIG. 3, surface-space fabric 300comprises surface fabric 320, space fabric 340, and one or more ofintermediary fabrics 380. Intermediary fabric 380 comprises a pluralityof intermediary networking nodes 370 interconnected via intermediarycommunication links 385. Preferably fabric 380 also comprisesintermediary manager 375 located on one of nodes 370.

As previously presented, space fabric 340 comprises a plurality ofspacecraft nodes 330 interconnected via spacecraft links 345. Spacemanager 335 can manage or establish a communication topology among nodes330. In a preferred embodiment, spacecraft nodes 330 are a constellationof GEO satellites interconnected via lasers where the satellites form anetwork fabric in space. One or more of spacecraft nodes 330 cancommunicate with intermediary nodes 370 or surface nodes 310 via up/downlinks 365.

Surface fabric 320 preferably comprises a plurality of surface nodes 310interconnected via surface communication links 325 as previouslydescribed. Surface manager 315 can manage or establish a communicationtopology among nodes 3 10. Surface nodes 310 can also communicate withintermediary nodes 370 or spacecraft nodes 330 via up/down links 365.

Intermediary networking nodes 370 of intermediary fabric 380 preferablyinclude objects located at an altitude between surface fabric 320 andspace fabric 340. Intermediary nodes 370 are preferably equipped tocommunicate with surface nodes 310 or spacecraft nodes 330. Nodes 370are contemplated to include powered flight craft (e.g., airplanes,blimps, etc . . . ) or non-powered flight craft (e.g., balloons,gliders, satellites, etc . . .).

Intermediary fabric 380 can include manager 370. However, manager 370 isnot necessary for the operation of intermediary fabric 380. Manager 370can establish a communication topology among nodes 370 as previouslydescribed.

Global manager 317 operates to configure a communication topology amongnodes 310, 330, and 370 in cooperation with local fabric managers,possibly including fabric manager 370.

One should note intermediary nodes 370, and by extension intermediaryfabric 380, is thought to have more dynamic links relative to fabrics320 or 340 due to the relevant movement of nodes 370 with respect toeach other, surface nodes 310, or spacecraft nodes 330. Although nodes370 are expected to move due to powered flight or non-powered flight,their movement can be predicted with sufficient accuracy that globalmanager 317 can establish port-to-port paths among all nodes. It isspecifically contemplated that paths within a global communicationtopology can include time dependencies where a path can have a temporalextent. For example, global manager 317 can establish a path thatincludes routes through an LEO satellite that has intermittentconnectivity with respect to specific surface nodes 310 or specificsurface nodes 330. Global manager 317 constructs a routing table thatincludes path information defining at which times a path is active orinactive, and disseminates the routing tables to the nodes of fabric300. The nodes of fabric 300 store the routing table and can utilizepaths when they are active. It should be noted that an active pathexists during an active period without requiring the path to beconstructed. Should a packet encounter a situation where a path is nolonger viable, a node can re-route the packet along a new path asdetermined by the routing table. Such an approach allows forestablishing a global communication topology among nodes having dynamiclinks without requiring global manager 317 or local managers toconstantly reconfigure the global or local communication topologies.Furthermore, the approach substantially reduces the need for sendingrouting table updates to all nodes when intermediary nodes 370 looseconnectivity.

A surface-space network fabric as presented provides severaladvantageous capabilities. Connectivity among nodes of the integratedfabric can retain connectivity when an up/down link is lost due tojamming, natural causes, or equipment failure. Data packets can beswitched to alternative paths around lost links or nodes. Additionally,paths within the fabric can be established in a deterministic fashionthrough a global fabric manger. Furthermore, intermediary nodes can bedeployed and integrated into the surface-space fabric to enhanceconnectivity, possibly during emergency circumstances including a firstresponse to a disaster or a military operation.

It should be apparent to those skilled in the art that many moremodifications besides those already described are possible withoutdeparting from the inventive concepts herein. The inventive subjectmatter, therefore, is not to be restricted except in the spirit of theappended claims. Moreover, in interpreting both the specification andthe claims, all terms should be interpreted in the broadest possiblemanner consistent with the context. In particular, the terms “comprises”and “comprising” should be interpreted as referring to elements,components, or steps in a non-exclusive manner, indicating that thereferenced elements, components, or steps may be present, or utilized,or combined with other elements, components, or steps that are notexpressly referenced. Where the specification claims refers to at leastone of something selected from the group consisting of A, B, C . . . andN, the text should be interpreted as requiring only one element from thegroup, not A plus N, or B plus N, etc.

1. A distributed surface-space network fabric, comprising: a spacenetwork fabric of networked spacecraft nodes interconnected viainter-spacecraft communication links, and including at least one of thespacecraft nodes functioning as a space fabric manager capable ofconfiguring a spacecraft communication topology among the spacecraftnodes; a surface network fabric of networking nodes interconnected viasurface communication links, including at least one of the surface nodesfunctioning as a surface fabric manager capable of configuring a surfacecommunication topology among the surface nodes, and where at least someof the surface nodes are communicatively coupled to at least some of thespacecraft nodes via up/down communication links; and a global fabricmanager configured to establish a global communication topology amongthe spacecraft and the surface nodes in cooperation with the space andthe surface fabric managers.
 2. The fabric of claim 1, wherein thesurface and the spacecraft nodes are fungible with respect to being theglobal fabric manager.
 3. The fabric of claim 2, wherein the globalmanager and at least one of the space and surface managers operate on acommon node selected from the surface and the spacecraft nodes.
 4. Thefabric of claim 1, wherein the space manager maintains coherency of thespacecraft topology upon loss of connectivity with the global fabricmanager.
 5. The fabric of claim 1, wherein the inter-spacecraft linkscomprise optical links.
 6. The fabric of claim 1, wherein the up/downlinks support a bandwidth of at least 10 Gbps.
 7. The fabric of claim 1,wherein the up/down links comprise aggregated links.
 8. The fabric ofclaim 1, further comprising intermediary networking nodes at an altitudebetween the surface fabric and the space fabric, and in communicationwith the surface and the space fabrics.
 9. The fabric of claim 8,wherein at least one of the intermediary nodes comprises a non-poweredflight craft.
 10. The fabric of claim 1, wherein at least one of thespacecraft nodes is in a geosynchronous orbit.
 11. The fabric of claim1, wherein the global topology comprises a path from a first physicalport on one of the spacecraft nodes to a second physical port on one ofthe surface nodes.
 12. The fabric of claim 1, wherein the spacecraftnodes comprise a fabric switching module configured to operate as thespace manager.
 13. The fabric of claim 12, wherein the switching modulecomprises a software update to the spacecraft nodes.
 14. The fabric ofclaim 12, wherein the space fabric comprises a distributed core fabric.15. The fabric of claim 14, wherein the spacecraft nodes comprise aredundant fabric switching module.
 16. The fabric of claim 1, whereinthe space manager, the surface manager, and the global manager canmigrate from a first networking node to a different networking node. 17.The fabric of claim 1, wherein the global fabric manager is administeredby an individual under authority of the United States government. 18.The fabric of claim 1, wherein at least one of the spacecraft nodes islocated at a LaGrange point.